Index: www/sites/all/modules/custom/scan_api/scan_api.module
===================================================================
--- www/sites/all/modules/custom/scan_api/scan_api.module	(revision 34204)
+++ www/sites/all/modules/custom/scan_api/scan_api.module	(working copy)
@@ -311,7 +311,17 @@
 
   array_push($params, $scan_id, $max_age);
   scan_api_set_active_shard('posts');
-  if ($total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params))) {
+
+  $total = dmemcache_get("sgi:$scan_id", 'pager');
+  // Hide this query behind memcache because it sucks.
+  if ($total === FALSE) {
+    $total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params));
+    if ($total > 1000) {
+      // This scan is nontrivial, don't constantly recalculate the item count.
+      dmemcache_set("sgi:$scan_id", $total, time() + 120, 'pager');
+    }
+  }
+  if ($total) {
     do {
       $items = array();
       scan_api_set_active_shard('posts');
@@ -574,7 +584,17 @@
 
   array_push($params, $scan_id, $max_age);
   scan_api_set_active_shard('posts');
-  if ($total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params))) {
+
+  $total = dmemcache_get("sti:$scan_id", 'pager');
+  // Hide this query behind memcache because it sucks.
+  if ($total === FALSE) {
+    $total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params));
+    if ($total > 1000) {
+      // This scan is nontrivial, don't constantly recalculate the item count.
+      dmemcache_set("sti:$scan_id", $total, time() + 120, 'pager');
+    }
+  }
+  if ($total) {
     do {
       $items = array();
       scan_api_set_active_shard('posts');
Index: view/sites/all/modules/scan_api/scan_api.module
===================================================================
--- view/sites/all/modules/scan_api/scan_api.module	(revision 34204)
+++ view/sites/all/modules/scan_api/scan_api.module	(working copy)
@@ -311,7 +311,17 @@
 
   array_push($params, $scan_id, $max_age);
   scan_api_set_active_shard('posts');
-  if ($total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params))) {
+
+  $total = dmemcache_get("sgi:$scan_id", 'pager');
+  // Hide this query behind memcache because it sucks.
+  if ($total === FALSE) {
+    $total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params));
+    if ($total > 1000) {
+      // This scan is nontrivial, don't constantly recalculate the item count.
+      dmemcache_set("sgi:$scan_id", $total, time() + 120, 'pager');
+    }
+  }
+  if ($total) {
     do {
       $items = array();
       scan_api_set_active_shard('posts');
@@ -574,7 +584,17 @@
 
   array_push($params, $scan_id, $max_age);
   scan_api_set_active_shard('posts');
-  if ($total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params))) {
+
+  $total = dmemcache_get("sti:$scan_id", 'pager');
+  // Hide this query behind memcache because it sucks.
+  if ($total === FALSE) {
+    $total = db_result(db_query("SELECT COUNT(*) FROM {scan_items} si " . $extra_join . " WHERE si.scan_id = %d AND si.created >= DATE_SUB(NOW(), INTERVAL %d SECOND)" . $extra_where, $params));
+    if ($total > 1000) {
+      // This scan is nontrivial, don't constantly recalculate the item count.
+      dmemcache_set("sti:$scan_id", $total, time() + 120, 'pager');
+    }
+  }
+  if ($total) {
     do {
       $items = array();
       scan_api_set_active_shard('posts');